RT Journal Article
T1 Bias driven coherent carrier dynamics in a two-dimensional aperiodic potential
A1 Moura, F. A. B. F., de
A1 Viana, L. P.
A1 Lyra, M. L.
A1 Malyshev, Andrey
A1 Domínguez-Adame Acosta, Francisco
AB We study the dynamics of an electron wave-packet in a two-dimensional square lattice with an aperiodic site potential in the presence of an external uniform electric field. The aperiodicity is described by epsilon(m) = V cos(pi alpha m(x)(nu x)) cos(pi alpha m(y)(nu y)) at lattice sites (m(x),m(y)), with pi alpha being a rational number, and v(x) and v(y) tunable parameters. controlling the aperiodicity. Using an exact diagonalization procedure and a finite-size scaling analysis, we show that in the weakly aperiodic regime (nu(x), nu(y) < 1), a phase of extended states emerges in the center of the band at zero field giving support to a macroscopic conductivity in the thermodynamic limit. Turning on the field gives rise to Bloch oscillations of the electron wave-packet. The spectral density of these oscillations may display a double peak structure signaling the spatial anisotropy of the potential landscape. The frequency of the oscillations can be understood using a semi-classical approach.
PB Elsevier
SN 0375-9601
YR 2008
FD 2008-10-27
LK https://hdl.handle.net/20.500.14352/51233
UL https://hdl.handle.net/20.500.14352/51233
LA eng
NO © 2008 Elsevier B.V. All rights reserved.Work at Alagoas was supported by CNPq-Rede Nanobioestruturas, CAPES (Brazilian research agencies) and FAPEAL (Alagoas State agency). Work at Madrid was supported by MEC (Project MOSAICO) and BSCH-UCM (Project PR34/07-15916).
NO CNPq-Rede Nanobioestruturas
NO CAPES
NO FAPEAL
NO MEC
NO BSCH-UCM
DS Docta Complutense
RD 6 abr 2025